The Marbles — those little bits of rubber that cars shed off the racing line and that, lap after lap, turn a clean circuit into a lived-in one.
No fake decals painted onto the track: here the marbles are 3d generated dynamically based on how everyone drives. Stay on the line and the groove stays clean; run wide, slide, take the kerbs, and you'll watch the rubber pile up exactly where it does in real life: just off the racing line.
Features
Dynamic generation — marbles are thrown from the tyres based on how far off the line you are and how much the tyres are scrubbing. On the line: almost none. Toward the edge: plenty.
The track "matures" — at race start the track is clean; rubber builds up gradually and reaches full intensity after roughly two laps, just like a real session.
Every car contributes — player and AI shed marbles the same way. After a few laps, the band of rubber at the track's edge is the work of the whole field.
Real 3D pebbles — low-poly bits with random tumbling rotation that flip through the air before settling (with an optional flat 2D fallback and batched rendering for performance).
Realistic redistribution — cars driving over the marble band relaunch some bits into the air and pick up others, just like on a real track.
Impact sound effect — when a marble thrown by the car ahead hits your car, you hear a sharp tick. Separate interior/exterior camera volumes, with customizable sounds.
Cosmetic only — no physics changes, client-side, works offline. Pit lane and grass/gravel are automatically excluded.
Configuration
Everything is tunable live from the app panel: intensity, "edge bias" (how tightly the band hugs the track edge), slide boost, AI on/off, 3D/2D pebbles, size, render distance, accumulation cap, and the impact-sound settings.
Extract the marbles folder into …/assettocorsa/apps/lua/, launch the game, and enable the Marbles app from the in-game app list.
Update
Material-based code implementation: .kn5 model is no longer required.
UI Configuration: Adjust brightness and pebble size (larger/smaller) directly from the interface.
Smoothness Toggle: Enable higher polygon counts via UI for smoother pebbles (reduces total pebble amount).
Enhanced Physics: Added new animations to allow pebble rebounding.